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arXiv · 1409.2795

Most spin-1/2 transition-metal ions do have single ion anisotropy

Jia Liu·Hyun-Joo Koo·Hongjun Xiang·Reinhard K. Kremer·Myung-Hwan Whangbo
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Abstract

The cause for the preferred spin orientation in magnetic systems containing spin-1/2 transition-metal ions was explored by studying the origin of the easy-plane anisotropy of the spin-1/2 Cu2+ ions in CuCl2.2H2O, LiCuVO4, CuCl2 and CuBr2 on the basis of density functional theory and magnetic dipole-dipole energy calculations as well as a perturbation theory treatment of the spin-orbit coupling. We find that the spin orientation observed for these spin-1/2 ions is not caused by their anisotropic spin exchange interactions, nor by their magnetic dipole-dipole interactions, but by the spin-orbit coupling associated with their crystal-field split d-states. Our study also predicts in-plane anisotropy for the Cu2+ ions of Bi2CuO4 and Li2CuO2. The results of our investigations dispel the mistaken belief that magnetic systems with spin-1/2 ions have no magnetic anisotropy induced by spin-orbit coupling.

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Jia Liu, Hyun-Joo Koo, Hongjun Xiang, Reinhard K. Kremer, Myung-Hwan Whangbo. 2014-09-12. Most spin-1/2 transition-metal ions do have single ion anisotropy. https://doi.org/10.1063/1.4896148

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